Airbags serve to protect occupants, in particular vehicle occupants, in the event of accidents. In the event of an accident, a folded airbag is filled with deployment gas via a gas generator, for example in the form of a compressed air reservoir or a pyrotechnic gas generator. The airbag is folded in a housing or in a shell, which is torn after activation of the gas generator, and is positioned between the user and the vehicle structure, for example a steering wheel or an instrument panel. In combination with a seatbelt, the airbag is a protection device that protects against impact with the vehicle structure or reduces the impact.
A prerequisite for the optimal functioning of the airbag is that it deploys promptly and completely between the user and the vehicle structure. The very small time period that is available is therefore further reduced if the user is not in the usual upright and reclined position but assumes a position deviating therefrom, in which the user is located closer to the vehicle structure. The so-called out-of-position (OOP) posture can cause the user to be impacted by the deploying airbag with a force counter to the direction of travel, which should be avoided.
In the case of a driver airbag, if the user's head is in the vicinity of the steering wheel, the airbag can be entrapped beneath the chin of the user or exert pressure on the chest. If deployment should be delayed, there is the possibility that the lower region of the steering wheel is not covered quickly enough, and the user can come into contact with the steering wheel.
In addition, there is the basic problem that space-saving folding must be provided, by which high repeatability of the deployment method can be realized with a small packaging space requirement.
DE 44 22 276 A1 relates to an airbag and a method for folding airbags wherein in a first step an essentially flatly spread, inflatable airbag is folded along main fold lines that run around an imaginary center. The airbag prefolded in this manner is subsequently at least partially folded or pressed into the desired final shape over secondary fold lines that cross the main fold lines.
The object of the present invention is to achieve secure deployment even in OOP situations, and in particular to provide a reduced risk of injury with a driver airbag having limited deployment possibilities.
This object is inventively achieved by a and an airbag unit as described herein.